Potential subjects will be identified by a brief screen combined with a short follow-up interview, the PRIME-MD that consists of two self-report items, as follows: “During the PAST MONTH, have you been bothered A LOT by (1) little interest or pleasure in doing things (yes or no) or (2) feeling down, depressed, or hopeless (yes or no).” If either item is scored “yes,” a short follow-up interview to establish a diagnosis is indicated. The two screen items yield a sensitivity of 69% and specificity of 82% when diagnoses made by a mental health professional are used as the criterion standard. Subjects will also have to have a general health questionnaire score > 5, indicating high levels of distress. Potentially eligible subjects will then undergo a structured clinical interview for diagnosis. Twenty, age, gender and cardiovascular risk level controls will be selected from the same population. Controls will be matched for age, sex and risk with the depressed subjects.